An experimental study of floating wick basin type vertical multiple effect diffusion solar still with waste heat recovery

In the present study, a floating wick basin type vertical multiple effect diffusion solar still with waste heat recovery (FW-BVMED-HR) has been constructed by modifying the conventional design of basin type VMED solar still (reference still). The reference still has been modified by incorporating improvements like multiple floating wicks in the basin and heat exchanger for waste heat recovery in order to determine the cumulative effect of both of these improvements. The performance of the FW-BVMED-HR still was compared with reference still under identical weather and operational conditions by running them side by side simultaneously. Both the stills were made of same dimensions and materials, and consisted of four effects. On a clear sunny day, the distillate productivity of FW-BVMED-HR still was found to be 21% higher than the reference still. High distillate productivity resulted, due to high convective heat transfer by humid basin air from high temperature float wick surface to first partition plate, feed water pre-heating from waste heat recovery, reduced basin bottom and side losses, and high night distillate productivity as a result of additional heat stored in multiple floating wicks.